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Use of Label-free Optical Biosensors to Detect Modulation of Potassium Channels by G-protein Coupled Receptors
Published on: February 10, 2014
Optofluidic microcapillary biosensor for label-free, low glucose concentration detection
Hongdan Wan1,2, Jijing Chen1, Cheng Wan3
1Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Abstract:
We demonstrate label-free detection of low glucose concentration based on whispery gallery mode resonance in an optofluidic microcapillary (OFMC) biosensor. The wall surface of the OFMC is bio-chemically functionalized to detect cellular-level glucose concentration as low as 2.78 mM. The measured sensitivity is 0.966 pm/mM. The fabricated microcapillary has a thin wall thickness of 2 μm and a Q factor of 1.3 × 106, corresponding to a bulk refractive index sensitivity of 23.36 nm/RIU. The OFMC biosensor has advantages such as high resistance to environmental perturbation, small sample volume down to 90 nL and cost-effectiveness. Theoretical analysis shows the sensor sensitivity depends on the microcapillary wall thickness and liquid core refractive index.
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